ABSTRACT Worldwide, there is a growing incidence of cancer with a present annual number of diagnosed cases at about 15 M. In 2016, the NCI estimates that in the US, 1,685,210 new cancers will be diagnosed that result in 595,690 deaths. Standard chemotherapy is often ineffective and is known for its numerous toxic side effects. Embolization therapy is highly selective to a particular tumor; whereby anti-cancer agents are largely confined within the tumor. Current delivery devices are inadequate, resulting in incomplete tumor filling, non-target delivery to healthy tissues, irreproducibility, and failure of the technique to reach its full efficacy potential. Presently, embolization therapy is largely limited to tumors of the liver. The objective of the present Phase II project is to substantially improve the efficacy and reproducibility of this technique and deliver a product to the market in relatively short period of time that expands embolization therapy to many cancers, offering lifesaving efficacy and dramatic improvements in the quality of life. Through hemodynamic studies, the company elucidated a mechanism whereby blood flow redistribution, enabled by a lowering of pressure in the vicinity of the tumor, results in embolic agents to preferentially flow into the tumor. The present Phase II proposal includes the design and implementation of a balloon microcatheter with integrated pressure microsensor. The unique partial occlusion balloon implements the required pressure reduction and includes flow-through channels that allow a small blood bypass of about 10% to wash anti-tumor agents from the infusion point to the tumor. The pressure sensor provides real-time pressure monitoring allowing embolization to be charted and optimized in real-time and include a quantitative endpoint. Existing microsensors will be modified and integrated at a position distal to the occlusion balloon. In parallel, the balloon will be optimized to the desired flow-through velocity and pressure reduction range of a 10?50 mmHg in the vascular space distal to the balloon. The catheter will be optimized to specifications required for clinical use including an outer diameter of less than 1 mm, excellent tracking through torturous vasculature, compatibility with common reagents and balloon inflation/deflation times of less than 15 seconds. The pressure sensor, catheter, and partial occlusion balloon will be integrated and assembled consistent with a manufacturing environment. Bench and animal testing will comply with FDA and CE requirements and will be included in a regulatory filing at the end of the Phase II period. An animal tumor model will be completed using a rabbit VX2 liver carcinoma. This model is well characterized and has been used in tumor embolization studies. The primary endpoint is to demonstrate that embolization at a low pressure, via partial occlusion, improves chemotherapeutic distribution, and tumor response (necrosis). Secondary objectives include correlation of pressure to tumor response and demonstrating a pressure mediated quantitative endpoint. This study will be helpful in marketing the device following the Phase II period.